Efficient production of L-asparaginase in Bacillus licheniformis by optimizing expression elements and host / 生物工程学报

L-asparaginase (L-ASN) is widely applied in the treatment of malignant tumor and low-acrylamide food production, however, the low expression level hampers its application. Heterologous expression is an effective strategy to increase the expression level of target enzymes, and Bacillus is generally used as the host for efficient production of enzymes. In this study, the expression level of L-asparaginase in Bacillus was enhanced through optimization of expression element and host. Firstly, five signal peptides (SPSacC, SPAmyL, SPAprE, SPYwbN and SPWapA) were screened, among which SPSacC showed the best performance, reaching an activity of 157.61 U/mL. Subsequently, four strong promoters (P43, PykzA-P43, PUbay and PbacA) from Bacillus were screened, and tandem promoter PykzA-P43 showed the highest yield of L-asparaginase, which was 52.94% higher than that of control strain. Finally, three Bacillus expression hosts (B. licheniformis Δ0F3 and BL10, B. subtilis WB800) were investigated, and the maximum L-asparaginase activity, 438.3 U/mL, was reached by B. licheniformis BL10, which was an 81.83% increase compared with that of the control. This is also the highest level of L-asparaginase in shake flask reported to date. Taken together, this study constructed a B. licheniformis strain BL10/PykzA-P43-SPSacC-ansZ capable of efficiently producing L-asparaginase, which laid the foundation for industrial production of L-asparaginase.

Comparison of Diagnostic Performance Between PI-RADS v2.1 and PI-RADS v2 for Prostate Cancer: A Meta-analysis / 肿瘤防治研究

Objective To compare the diagnostic performance of PI-RADS v2.1 and PI-RADS v2 in the detection of clinically significant prostate cancer(csPCa) by Meta-analysis. Methods The major biomedical databases were searched (CNKI, CBM, Medline, and Embase) with the keywords "PIRADS v2.1" or "PI-RADS v2.1". The Quality Assessment of Diagnostic Accuracy Studies Tool v2 (QUADAS-2) was used to evaluate literature quality. Meta-analysis was performed using STATA17.0 and ReMan5.4 software. Forest plots were used to represent the sensitivity and specificity of PI-RADS v2.1 and PI-RADS v2 for each study. Sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were combined, and diagnostic performance was evaluated using asummary receiver operating characteristic curve (SROC). Subgroup analysis was performed on three covariables: tumor location, threshold, and the nationality of authors. Results A total of 12 studies were included, involving 3 158 patients and 3 243 lesions. Forall zones and the whole gland, PI-RADS v2.1 had a larger area under the SROC curve (AUC) for csPCa performance, compared with PI-RADS v2. Subgroup analysis: PI-RADS v2.1 also had a larger area under the SROC (AUC) to detect transitional zone csPCa. Different diagnostic thresholds: when a score of 4 was used for the threshold, PI-RADS v2.1 had the maximum area under SROC (AUC) for csPCa performance detection. Author nationality: Researches of PI-RADS v2.1 in Chinese authors had the largest area under the SROC (AUC) in detecting csPCa performance. Conclusion Compared with PI-RADS v2, the diagnostic performance of PI-RADS v2.1 in detecting csPCa is not obviously improved and overall specificity is still low.

Protective effect and mechanism of Artemisia argyi extract on vancomycin-induced acute kidney injury / 中国药科大学学报

@#The goal of the study was to investigate the protective effect and mechanism of Artemisia argyi ethanol extract on chemotherapeutic vancomycin (VAN)-induced acute kidney injury (AKI).The acute kidney injury model of male ICR mice was induced by intraperitoneal injection (ip) of VAN.Thirty mice were divided into the blank group, model group, high dose group, middle dose group and low dose group, which were given medicine by gastric perfusion (ig).Serum levels of cystain C (Cys C), blood urea nitrogen (BUN) and serum creatinine (Scr) were measured, which could reflect renal function of mice.Serum oxidative stress and inflammation indices were also determined, including muscular dystrophy association (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), tumor necrosis factor-alpha (TNF-α), Interleukin-1β (IL-1β), and high-sensitive c-reactive protein (hs-CRP).In addition, hematoxylin-eosin staining (HE) was employed for measuring the damage of renal tissues and the content of apoptosis b-cell lymphoma-2 (Bcl-2), Bcl-2 assaciated X protein (Bax) and caspase-3 were measured too.All results showed that Artemisia argyi extract exhibits protective effect on chemotherapeutic VAN-induced AKI, whose mechanism could be related to the oxidative stress, inflammatory reaction and apoptosis.

Effect of Artemisia Argyi Folium ethanolic extract on blood glucose and blood lipids in diabetic mice / 中国药科大学学报

@#To investigate the effect of ethanolic extract from Artemisia Argyi Folium on blood glucose and blood lipids in diabetic mice, ICR mice were induced by intraperitoneal injection of 35 mg/kg streptozotocin (STZ) and a high-carbohydrate/high-fat diet to construct type 2 diabetes mellitus model. Diabetic mice were randomly divided into three groups: the model group (5 mL/kg 0.5% CMC-Na), the Artemisia Argyi Folium ethanolic extract low-dose group (100 mg/kg ) and high-dose group (400 mg/kg ). During the treatment for 6 weeks, the amount of drinking water and food intake of mice were recorded every day. Blood glucose and body weight were recorded every week. After treatment for 6 weeks, serum total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C),and oral glucose tolerance (OGTT) were measured. The results showed that the amount of drinking water and food intake of mice significantly decreased (P < 0.01) in the Artemisia Argyi Folium ethanolic extract high-dose group; oral glucose tolerance was significantly improved (P < 0.01) and the contents of TC, TG and LDL-C were significantly decreased in the Artemisia Argyi Folium ethanolic extract low-dose group (P < 0.01). The ethanolic extract from Artemisia Argyi Folium could significantly improve the glucose and lipid metabolic disorder in T2DM mice in a dose-dependent manner.

Degradation of proteins by PROTACs and other strategies

Blocking the biological functions of scaffold proteins and aggregated proteins is a challenging goal. PROTAC proteolysis-targeting chimaera (PROTAC) technology may be the solution, considering its ability to selectively degrade target proteins. Recent progress in the PROTAC strategy include identification of the structure of the first ternary eutectic complex, extra-terminal domain-4-PROTAC-Von-Hippel-Lindau (BRD4-PROTAC-VHL), and PROTAC ARV-110 has entered clinical trials for the treatment of prostate cancer in 2019. These discoveries strongly proved the value of the PROTAC strategy. In this perspective, we summarized recent meaningful research of PROTAC, including the types of degradation proteins, preliminary biological data in vitro and in vivo, and new E3 ubiquitin ligases. Importantly, the molecular design, optimization strategy and clinical application of candidate molecules are highlighted in detail. Future perspectives for development of advanced PROTAC in medical fields have also been discussed systematically.

Chemical constituents of total alkaloids from Picrasma quassioides and its effects on collagen induced arthritis in rats / 中国药科大学学报

@#This study aimed to investigate the effects of total alkaloids from Picrasma quassioides(TAPQ)on collagen-induced arthritis(CIA)in rats. TAPQ were prepared by acid extraction and alkali precipitation. The qualitative analysis of TAPQ by HPLC-Q-TOF-MS/MS was carried out. Fourteen alkaloids were obtained and three of them were quantitatively analyzed by HPLC. The anti-inflammatory activity of TAPQ was investigated on RAW264. 7 induced by LPS. Dexamethasone was used as a positive control. The model of bovine type II collagen-induced rheumatoid arthritis in SD rats was established. Daily tail intravenous injection of 0. 907 or 1. 814 mg/kg of TAPQ was administered for 18 days continuously, using dexamethasone as a positive control. The changes of mean arthritis scores in the paw of the rats and the volume of the paw were measured every day. Compared with the model group, the TAPQ significantly reduced the degree of paw swelling(P< 0. 001). After the rats were sacrificed, the levels of TNF-α and IL-6 in the serum were measured. The TAPQ could significantly reduce the level of TNF-α(P< 0. 01)and IL-6(P< 0. 001). The pathological changes of the joints were observed by HE staining, the anti-inflammatory activity of TAPQ was good, and the degree of joint damage in rats was obviously reduced.

Application of telemedicine robot in follow-up after liver transplantation from donation after cardiac death / 器官移植

Objective To evaluate the application effect of telemedicine robot on the postoperative follow-up of liver transplantation recipients from donation after cardiac death (DCD). Methods A total of 100 recipients undergoing liver transplantation from DCD in the First Affiliated Hospital of Xi 'an Jiaotong University from January 2014 to December 2017 were recruited in this investigation. According to differnt follow-up patterns, all recipients were divided into the research group (n=50, follow-up by telemedicine robot) and control group (n=50, follow-up by traditional telephone). The compliance (medication compliance, self-monitoring, life compliance and follow-up compliance), follow-up time and follow-up satisfaction at postoperative 3 months of all DCD liver transplantation recipients were analyzed and statistically compared between research group and control group. Results The scores of medication compliance, self-monitoring, life compliance, follow-up compliance and the total score of compliance in the research group were significantly higher than those in the control group (all P < 0.05). The each follow-up time of liver transplantation recipients in the research group was (9±4) min, significantly shorter than (13±4) min in the control group (t=-4.452, P < 0.001). The score of satisfaction during postoperative follow-up in the research group was 19.8±2.6, significantly higher than 16.2±3.1 in the control group (t=6.234, P < 0.001). Conclusions The application effect of telemedicine robot on the postoperative follow-up of liver transplantation recipients from DCD is satisfactory, deserves widespread application in clinical practice. It is expected to become an indispensable part of the postoperative follow-up of liver transplantation recipients from DCD.

Acute kidney injury induced by hypothyroidism myopathy: a clinical analysis of 24 cases / 中华全科医师杂志

Clinical data of 24 patients with acute kidney injury (AKI) induced by hypothyroidism myopathy admitted in our hospital from January 2014 to December 2016 were analyzed retrospectively.There were 9 patients classified as AKI stage Ⅰ and 15 patients as AKI stage Ⅱ according to the Kidney Disease Improving Global Outcomes (KDIGO),21 hypothyroidism myopathy patients without AKI were selected as control group.ANOVA and chi-square test were used to compare the general data and laboratory results among three groups;artificial neural network analysis and multi-factor stepwise regression method were used to analyze the factors related to AKI.There were significant differences in serum creatinine (Scr) (F=34.3,P＜0.01),BUN(F=29.1,P＜0.01),ALB(F=5.27,P=0.01),CK(F=8.61,P=0.01),creatin kinase isoenzyme(CK-MB)(F=33.1,P＜0.01),LDH(F=7.78,P=0.01),ALT(F=34.3,P＜0.01) and AST (F=28.1,P＜0.01) among three groups.Artificial neural network analysis showed that myoglobin was closely related to serum creatinine,suggesting its importance for AKI in patients with primary hypothyroidism myopathy.Multivariate regression analysis showed that serum creatinine was correlated with CK-MB(B=2.10,SE=0.38,β=0.96,t=5.52),LDH(B=0.18,SE=0.06,β=0.34,t=3.00)and AST(B=0.16,SE=0.09,β=0.32,t=2.62).This study indicates that hypothyroidism myopathy may be one of the causes of AKI,and the severity of AKI might be closely related to the severity of hypothyroidism myopathy.

Total phenolic contents and bioactivities of defatted Vitellaria paradoxa kernels from different origin / 中国药科大学学报

@#Total phenolic contents, antioxidant, cytotoxic and Epstein-Barr virus early antigen(EBV-EA)inhibitory activities of twenty-six methanol extracts from defatted Vitellaria paradoxa kernel at different sites were investigated. Furthermore, the correlation between total phenolic contents and bioactivities was discussed. The total phenolic contents were determined spectrometrically and antioxidant activities were evaluated by 1, 1-diphenyl-2-picrylhydrazyl(DPPH), 2, 2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid(ABTS)radical scavenging activity and ferric-reducing antioxidant power(FRAP)methods. The cytotoxic activities against human leukemia HL60 cells, lung cancer A549 cells and breast cancer SK-BR-3 cells were assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl-2H-tetrazolium bromide(MTT)assay and the inhibitory effect on EBV-EA was assayed by the indirect immunofluorescence technique. Results showed that the total phenolic contents of twenty-six methanol extracts were different(25. 8 - 265. 7 mg GAE/g DW). In addition, some of the extracts had potent antioxidant activities(DPPH: IC50 3. 4 - 54. 9 μg/mL, ABTS: 1. 11- 4. 09 mmol TE/g, FRAP: 1. 24 - 1. 93 mmol TE/g), toxicities against one or more of HL60, A549 and SK-BR-3 cells(IC50 25. 1- 95. 5 μg/mL)and inhibitory effect on EBV-EA(85. 8%- 94. 9% at 100 μg/mL). A significant correlation was observed between total phenolic contents and antioxidant activities(r=0. 750-0. 837, P< 0. 01).

Investigation of herb-drug interaction between Liuwei Dihuang Pills and nifedipine based on rat liver microsomes and HPLC fingerprints / 中国药科大学学报

@#A new method based on rat liver microsomes and chromatographic fingerprint comparison was established to investigate the possible herb-drug interactions between Liuwei Dihuang Pills(LDP)and nifedipine(NIF). LDP and NIF were incubated simultaneously with rat liver microsomes at 37 °C for 60 min in a shaking water bath. The separation was achieved on a C18 column using 0. 1% formic acid solution and acetonitrile as mobile phase with a liner gradient program. The flow rate was set at 1. 0 mL/min. Detection was achieved by UV light at 240 nm. To evaluate the interactions between LDP and NIF, the similarity of the fingerprinting chromatograms before and after co-incubation was calculated by similarity evaluation system for chromatographic fingerprint of TCM. Furthermore, pharmacokinetic experiments in rat suggested that there was no significant difference in the pharmacokinetic parameters of the typical components in LDP.

Correlations of serum prealbumin and albumin with the short-term outcomes in patients with acute ischemic stroke in different age groups / 国际脑血管病杂志

Objective To investigate the correlations of serum prealbumin and albumin with the shortterm outcome in patients with acute cerebral infarction in different age groups.Methods Patients with acute ischemic stroke admitted to hospital with 48 h were prospectively enrolled in the study.The modified Rankin Scale was used to assess the functional outcomes at 14 d after onset,0-2 was defined as a good outcome.According to the age of the patients,they were divided into either a young and middle-aged group (＜ 60 years) or an elderly group (≥60 years).The demography,baseline clinical data and laboratory findings of the patients were compared in the overall patients and the different age groups between the good outcome group and the poor outcome group.Multivariate logistic regression analysis was used to determine the independent influencing factors of short-term outcomes.Results A total of 622 patients with acute ischemic stroke were enrolled,including 402 (64.6％) males and 220 (35.4％) females;206 (33.1％) were in the young and middle-aged group,and 416 (66.9％) were in the elderly group;310 (49.8％) had good outcomes and 312 (50.2％) had poor outcomes.There were significant differences in the proportions of patients in male,old people,hyperlipidemia,diabetes mellitus,history of previous stroke or transient ischemic attack (TIA),as well as age,body mass index,levels of prealbumin,albumin,triglyceride,high-density lipoprotein cholesterol low-density lipoprotein cholesterol total bilirubin,direct bilirubin,indirect bilirubin,urea nitrogen,and uric acid between the good outcome group and the poor outcome group (all P ＜0.05).Multivariate logistic regression analysis showed that the female (odds ratio [OR] 1.522,95％ confidence interval [CI] 1.023-2.266;P =0.038),diabetes (OR 1.789,95％ CI 1.171-2.735;P =0.007) and higher low-density lipoprotein cholesterol (OR 1.251,95％ CI 1.017-1.539;P =0.034),total bilirubin (OR 1.054,95％ CI 1.029-1.081;P＜0.001),urea nitrogen (OR 1.245,95％ CI 1.100-1.409;P=0.001),and baseline National Institutes of Health Stroke Scale (NIHSS) score (OR 2.854,95％ CI 1.027-3.628;P =0.019) were the independent risk factors for poor outcomes,and higher prealbumin (OR 0.798 95％ CI 0.633-0.979;P =0.034) and albumin (OR 0.741,95％ CI 0.693-0.988;P =0.020) were the independent predictors of good outcomes.In the young and middle-aged patients,there were significant differences in the proportions of patients with small artery occlusion as well as age,triglyceride,and high-density lipoprotein cholesterol levels between the good outcome group and the poor outcome group (all P ＜0.05);multivariate logistic regression analysis showed that diabetes (OR 2.343 95％ CI 1.127-4.871;P=0.023) and higher baseline NIHSS scores (OR 2.041,95％ CI 1.304-4.125;P =0.027) were the independent risk factors for poor outcome,and higher high-density lipoprotein cholesterol (OR 0.742 95％ CI 0.639-0.937;P =0.044)was an independent predictor for good outcome.In the elderly patients,there were significant differences in the proportions of patients in male,previous stroke or TIA,and cardiogenic embolism,as well as prealbumin,low-density lipoprotein cholesterol,total bilirubin,direct bilirubin,indirect bilirubin,and uric acid levels between the good outcome group and the poor outcome group (all P ＜ 0.05);multivariate logistic regression the analysis showed that diabetes (OR 2.797,95％ CI 1.153-4.756;P =0.039),higher baseline NIHSS score (OR 2.586,95％ CI 1.033-3.435;P =0.035) and higher low-density lipoprotein cholesterol (OR 1.304,95％ CI 1.027-1.656;P =0.029) were the independent risk factors for poor outcome,and higher prealbumin was an independent predictor for good outcome (OR 0.795,95％ CI 0.691-0.998;P =0.002).Conclusions Prealbumin and albumin are the independent predictors for short-term good outcome in patients with acute ischemic stroke.The protective effect of serum prealbumin is more obvious in the elderly population (≥60 years).

Correlations of serum prealbumin and albumin with the short-term outcomes in patients with acute ischemic stroke in different age groups / 国际脑血管病杂志

Objective To investigate the correlations of serum prealbumin and albumin with the shortterm outcome in patients with acute cerebral infarction in different age groups.Methods Patients with acute ischemic stroke admitted to hospital with 48 h were prospectively enrolled in the study.The modified Rankin Scale was used to assess the functional outcomes at 14 d after onset,0-2 was defined as a good outcome.According to the age of the patients,they were divided into either a young and middle-aged group (＜ 60 years) or an elderly group (≥60 years).The demography,baseline clinical data and laboratory findings of the patients were compared in the overall patients and the different age groups between the good outcome group and the poor outcome group.Multivariate logistic regression analysis was used to determine the independent influencing factors of short-term outcomes.Results A total of 622 patients with acute ischemic stroke were enrolled,including 402 (64.6％) males and 220 (35.4％) females;206 (33.1％) were in the young and middle-aged group,and 416 (66.9％) were in the elderly group;310 (49.8％) had good outcomes and 312 (50.2％) had poor outcomes.There were significant differences in the proportions of patients in male,old people,hyperlipidemia,diabetes mellitus,history of previous stroke or transient ischemic attack (TIA),as well as age,body mass index,levels of prealbumin,albumin,triglyceride,high-density lipoprotein cholesterol low-density lipoprotein cholesterol total bilirubin,direct bilirubin,indirect bilirubin,urea nitrogen,and uric acid between the good outcome group and the poor outcome group (all P ＜0.05).Multivariate logistic regression analysis showed that the female (odds ratio [OR] 1.522,95％ confidence interval [CI] 1.023-2.266;P =0.038),diabetes (OR 1.789,95％ CI 1.171-2.735;P =0.007) and higher low-density lipoprotein cholesterol (OR 1.251,95％ CI 1.017-1.539;P =0.034),total bilirubin (OR 1.054,95％ CI 1.029-1.081;P＜0.001),urea nitrogen (OR 1.245,95％ CI 1.100-1.409;P=0.001),and baseline National Institutes of Health Stroke Scale (NIHSS) score (OR 2.854,95％ CI 1.027-3.628;P =0.019) were the independent risk factors for poor outcomes,and higher prealbumin (OR 0.798 95％ CI 0.633-0.979;P =0.034) and albumin (OR 0.741,95％ CI 0.693-0.988;P =0.020) were the independent predictors of good outcomes.In the young and middle-aged patients,there were significant differences in the proportions of patients with small artery occlusion as well as age,triglyceride,and high-density lipoprotein cholesterol levels between the good outcome group and the poor outcome group (all P ＜0.05);multivariate logistic regression analysis showed that diabetes (OR 2.343 95％ CI 1.127-4.871;P=0.023) and higher baseline NIHSS scores (OR 2.041,95％ CI 1.304-4.125;P =0.027) were the independent risk factors for poor outcome,and higher high-density lipoprotein cholesterol (OR 0.742 95％ CI 0.639-0.937;P =0.044)was an independent predictor for good outcome.In the elderly patients,there were significant differences in the proportions of patients in male,previous stroke or TIA,and cardiogenic embolism,as well as prealbumin,low-density lipoprotein cholesterol,total bilirubin,direct bilirubin,indirect bilirubin,and uric acid levels between the good outcome group and the poor outcome group (all P ＜ 0.05);multivariate logistic regression the analysis showed that diabetes (OR 2.797,95％ CI 1.153-4.756;P =0.039),higher baseline NIHSS score (OR 2.586,95％ CI 1.033-3.435;P =0.035) and higher low-density lipoprotein cholesterol (OR 1.304,95％ CI 1.027-1.656;P =0.029) were the independent risk factors for poor outcome,and higher prealbumin was an independent predictor for good outcome (OR 0.795,95％ CI 0.691-0.998;P =0.002).Conclusions Prealbumin and albumin are the independent predictors for short-term good outcome in patients with acute ischemic stroke.The protective effect of serum prealbumin is more obvious in the elderly population (≥60 years).

Urotensin Ⅱ promotes collagen expression in rats cardiac tissues and proliferation of cardiac myofibroblasts in new-born rats / 基础医学与临床

Objective To investigate the effect of urotensin Ⅱ on myocardial fibrosis in rats.Methods The pressure overload animal model was established in rats by abdominal aorta coarctation.The rats were divided into sham operation group,modeled for 4,8 and 12 weeks group.The expression of U Ⅱ,GPR14,col-Ⅰ,col-Ⅲ,and PKA in cardiac tissues was detected by Western blot.Isolated and cultured cardiac myofibroblasts (CFs) from new-born SD rats were treated with U Ⅱ,KT5720 or SB-611812,and then the proliferation of CFs was observed by micro scope and CKK-8.Results The expression of U Ⅱ,GPR14,col-Ⅰ,col-Ⅲand PKA increased markedly in cardiac tissues of model rat,which were time-dependent.U Ⅱ promoted the proliferation of CFs (P＜0.05),which could be inhibited by KT5720 or SB-611812.Conclusions U Ⅱ/UT system promotes the occurring and development of myocardial fibrosis.

Comparison of the Undergraduate Education for Pharmaceutical Analysis Between National University of Singapore and China Pharmaceutical University / 医药导报

The course of pharmaceutical analysis for pharmacy undergraduate students in National University of Singapore and China Pharmaceutical University was compared, in terms of curriculum, lecturing, assessment and practical teaching.This study provides in-depth analysis by the lecturers from both universities,and can provide reference for teaching reform and course construction of pharmaceutical analysis.

Correlation of Ki-67 expression with MRS metabolism in low-and high-grade cerebral gliomas / 中国肿瘤临床

objective:To investigate the relationship between magnetic resonance spectroscopy (MRS) metabolism and Ki-67 expres-sion in high-(HGG) and low-grade gliomas (LGG) by analyzing Ki-67 expression and HGG and LGG metabolites. Methods:We consid-ered 56 pathologically confirmed glioma cases in our hospital. The Ki-67 expression and the MRS metabolism parameters in the tu-mors were analyzed simultaneously. Results:The tumor solid value of Cho was positively correlated with the Ki-67 expression level (rs=0.714, P<0.05). By contrast, the Ki-67 expression level was negatively correlated with the tumor solid value of NAA (rs=?0.708, P<0.05) in 35 cases of the LGG group. The tumor solid value of Cho was also positively correlated with the Ki-67 expression level (rs=0.624, P<0.05). By comparison, the Ki-67 expression level was negatively correlated with the tumor solid value of NAA in the HGG group (rs=?0.769, P<0.05). Conclusion:The MRS metabolism was correlated with the Ki-67 expression in high-and low-grade gliomas.

Correlation of 3D ASL perfusion index with the expression of VEGF and MVD in glioma / 中国肿瘤临床

Objective:To investigate the correlation of the relative cerebral blood flow (rCBF) of three dimensional arterial spin labeling (3D ASL) with vascular endothelial growth factor (VEGF) expression and microvessel density (MVD) in glioma. Methods:Fifty-three glio-ma patients confirmed by pathology were subjected to conventional, enhanced MR and 3D ASL imaging before operation to deter-mine VEGF expression and MVD levels in each patient. The correlations of rCBF with VEGF expression and MVD in glioma were evaluat-ed, respectively. Results:rCBF was noted to be positively correlated to VEGF expression and MVD in glioma. The rs were 0.728 (VEGF) and 0.620 (MVD), respectively (P<0.05). Conclusion:The positive correlation of rCBF with VEGF expression and MVD in glioma implied that 3D ASL is beneficial for evaluating microvessel angiogenesis in glioma prior to surgery. This finding is significant for developing clin-ical treatment plans and for assessing patient prognoses.

IC-kmedoids: a clustering algorithm for RNA secondary structure prediction / 生物医学工程学杂志

Due to the minimum free energy model, it is very important to predict the RNA secondary structure accurately and efficiently from the suboptimal foldings. Using clustering techniques in analyzing the suboptimal structures could effectively improve the prediction accuracy. An improved k-medoids cluster method is proposed to make this a better accuracy with the RBP score and the incremental candidate set of medoids matrix in this paper. The algorithm optimizes initial medoids through an expanding medoids candidate sets gradually. The predicted results indicated this algorithm could get a higher value of CH and significantly shorten the time for calculating clustering RNA folding structures.

Application of improved locally linear embedding algorithm in dimensionality reduction of cancer gene expression data / 生物医学工程学杂志

Cancer gene expression data have the characteristics of high dimensionalities and small samples so it is necessary to perform dimensionality reduction of the data. Traditional linear dimensionality reduction approaches can not find the nonlinear relationship between the data points. In addition, they have bad dimensionality reduction results. Therefore a multiple weights locally linear embedding (LLE) algorithm with improved distance is introduced to perform dimensionality reduction in this study. We adopted an improved distance to calculate the neighbor of each data point in this algorithm, and then we introduced multiple sets of linearly independent local weight vectors for each neighbor, and obtained the embedding results in the low-dimensional space of the high-dimensional data by minimizing the reconstruction error. Experimental result showed that the multiple weights LLE algorithm with improved distance had good dimensionality reduction functions of the cancer gene expression data.

MicroRNA target predicition based on SVM and the optimized feature set / 生物医学工程学杂志

MicroRNA (miRNA) is a family of endogenous single-stranded RNA about 22 nucleotides in length. Through targeting 3' UTR of message RNA (mRNA), they play important roles in post-transcriptional regulatory functions. For further research of miRNA function, the identification of more miRNA positive targets is needed urgently. Aiming at the high-dimensional small sample data sets in miRNA target prediction, an algorithm of eliminating redundant features is proposed based on v-SVM in this paper, and classification and features selection are also fused. The algorithm of eliminating redundant features optimizes the combination of features, and then constructs the best features combination which can represent miRNA and targets interaction model. The prior parameter v (0 < u < or = 1) controls the compression proportion of data set and selects more distinguishing support vectors. Finally, the classifier model of miRNA target prediction is built. The unbiased assessment of the classifier is achieved with a completely independent test dataset. Experiment results indicated that in both classification recognition and generalization performance of miRNA targets predicition, this model was superior to the present machine learning algorithms such as miTarget, NBmiRTar and TargetMiner, etc.

Causes of vocal cord dyscinesia and its original factors after endotracheal intubation / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To research the causes of postintubation vocal cord dyskinesia and its contributing factors.@*METHOD@#The causes of vocal cord dyskinesia were confirmed by laryngoscope, three-dimensional spiral CT, stroboscope, and the analysis of therapy. The factors relevant to the causes of vocal cord dyskinesia were analysed based on the following elements: (1) the anatomic or pathological condition of patients or the technical skills of anesthetists. (2) emaciated or obese body and neck. (3) the age of patients. (4) the duration of endotracheal tube retention. (5) the types of operations. (6) anesthesia procedure.@*RESULT@#Among 135 patients, 128 cases (94.81%) manifested arytenoid dislocation, 7 cases (5.19%) vocal cord paralysis. The study showed that the vocal cord dyskinesia associated with anatomic or pathological condition of patients and technical skills of anesthetists (with intubation difficulty) accounted for 76.30%. The patients with relative emaciated body or neck accounted for 90.62% in cases without intubation difficulty. Age had no significant analytical relationship with vocal cord dyskinesia. Prolonged intubation (endotracheal tube retention over 12 hours) was accounted for only 17.64%. The incidence of vocal cord dyskinesia was nearly 0.5% in patients underwent cardio-thoracic surgery, accounting for 59.26% of all the patients.@*CONCLUSION@#There are two major causes of vocal cord dyskinesia: arytenoid dislocation and vocal cord paralysis, and the rate of vocal cord dyskinesia could be reduced by the improvement of technical skill of anesthetists and/or sufficient attention to the intubation condition of patients.